The present invention relates to a new and improved method of manufacturing monolithic integrated semiconductor devices and improved semiconductor devices manufactured according to the inventive method.
In the manufacture of customer specified integrated circuits, particularly in small and medium quantities, a pre-fabricated silicon wafer is used, distinguished by a multiplicity of P and N (or N and P) structures with contacts through a silicon-oxide layer; and an aluminium electrically conductive film thereon, forming electrical connections between the said P and N structures. The connection between contact surface and aluminium film occurs via so-called contact windows in the oxide layer which are arranged more or less regularly, and are visible in the aluminium film, and whose area forms a complete or partial conductive link (a so-called ohmic contact) with the contact surface.
It is well-known that the specialist, making use of electrical connections between the individual contact surfaces (in the XY plane), can create logical or linear circuits.
The required conductive areas are created through use of a well-known photo-etch technique, which requires a relatively expensive photo mask.
This known technique requires a relatively large expenditure, in that the photomask must be specially manufactured for each and every application.